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How to Make a Sinking Ship Birthday Cake – A Pretty Titanic Task

This post is a little different from my usual blog entries, but as the product combined mathematics and art, was definitely sweet, and can serve as an aid to anyone else who gets the tricky request for a Sinking Ship birthday cake, I feel justified in including here.

I must note that I am not including the recipe for the cake here, any preferred sponge or lamington cake can be used (if there are any requests for the specific cake used for the cake we made, I’ll be happy to add it separately). Also, all icing used was simple butter icing, made as firm as necessary to work with the different cake parts. Update: The recipe for the cakes used for this project is now included on the blog at Mum’s “Isabella’s Rectangle Cake”.

Before going into the details of the exercise (and trust me, an exercise is pretty much what it is!) I think a little back story is in order:

I have very creative and intelligent young nephew. He is also a young man with very clear and rather single-minded ideas about what he wants. This is a formidable combination, both a delight and a challenge. It manifests particularly in his requests for his birthday cake each year, for which his gran – my mother, a long-time baker of note – has somewhat bemusedly taken responsibility, with my assistance. Over the years we have produced, among others, a 3D Thomas the Tank Engine, two 3D Space Rockets (each quite different, of course), and a Lego cake consisting of large Lego blocks, small Lego blocks and a Lego Man.

Each year mom offers a nice simple idea, which is graciously acknowledged by the young man, before he makes an even trickier and more unexpected request than the year before (sort of like birthday poker: I see your idea, and raise you with my one). This year was no exception. On the contrary, in response to mom’s suggestion of a cake consisting of two decorated “one’s” for his eleventh birthday cake, he requested a sinking ship. Not for him just a ship, oh no, it had to be sinking.

Just one other aside: these requests are made for a birthday that is three days before Christmas, in a family where Christmas preparations start in November.

And so it began…

Step one was my usual visit to the internet to get ideas for our creation. I must admit, I was quite surprised at how many children seem to make this request. The sinking ship/ Titanic going down cake is not as strange as you may think, and there were quite a few pictures of cakes with the theme, both homemade and sold by professionals. What was lacking, though, were instructions on how to construct such a cake. The few examples that did give some guidance tended to use puffed rice treats for large parts, which we did not want to do.

So, it was back to the drawing board. (Actually, come to think of it, it was first time to the drawing board.)

My primary role in assisting mom with these cakes is design and construction, and this time was no different. The challenge I set myself was to have an all-cake structure that would be stable, self-supporting and have no risk of any parts collapsing. I also had to base the design on the size of the cake mom was going to bake.

Mom’s layer cake measures 18 x 30 cm and about 3cm high. With this as the basis, I guessed that we could create a reasonably sized half-ship. To be more certain, and to have a tangible guide for cutting the cake as needed, I imitated my design ideas on PowerPoint. This worked really well, and confirmed how the cake should be built. It also indicated that the entire ship could be made from the single layer, by doubling the layer, and using half the doubled cake for the hull and lower decks, and the other half for the upper decks and other elements. Designing it on paper really helped to ensure that what was in my head could actually be transferred to the cake in reality.

Required:

1 x 18 x 30 cm layer cake for the ship

1 x 18 x 30 cm layer cake for the sea (optional)

Foil covered cake board

Sharp knife with a long blade (long enough that the cake can be sliced in one motion)

Butter Icing (mix a nice big bowl using icing sugar, butter and milk, adding warm water to thin if necessary. From this base, scoop out little bits into smaller bowls to mix the colours as needed)

Lots of little bowls and teaspoons for mixing different colours of icing

Smooth narrow knife for icing the cake

Icing gun/ bag for the railing

Butter icing:

Uncoloured for sandwiching and “sticking” elements together

Light brown for the deck (add the slightest bit of cocoa)

Black for the hull and chimney stacks (we didn’t have black colouring, so mom carefully perfected a mix of blue food colouring and cocoa)

We used paper templates, based on the PowerPoint design, but adjusted to the size of the cake as we worked with it, to guide cutting and shaping. This worked really well.

Note – the ship can be made directly on a foil-covered board, which can then be iced for the “sea”, in which case, the single layer of cake is sufficient. However, while looking as good, this may not provide enough cake for eating (and really, isn’t that the point of cake?) We therefore used a second layer cake as the base.

As can be seen from the PowerPoint drawings above, and the actual cake cutting pictures that follow:

The cake is cut in half across the length (30cm side) and the two halves are iced together, one half on top of the other, bottom to bottom.

The doubled cake is then cut diagonally – very carefully with a long-blade knife- along the 18cm side, from bottom corner to top corner. We did this in a few steps so that we were cutting a shorter distance at a time:

Using a paper triangle – measured to the cake – as a guide, cut downwards into the cake at the middle-point of the triangle. Remove the back half of the top layer. (At this point we debated whether it was a waste icing the parts together totally first, as removing the top piece at this stage seemed to waste icing. However, it did stop the cake from wobbling or moving during cutting, and we reused some of the icing or used it to sandwich smaller pieces needed elsewhere, so we were happy we did it that way.)

Follow the bottom acute part of the triangle with the knife to cut the “back end” of the ship.

Carefully angling the knife once again, cut from the middle-point upwards to the top angle of the triangle.

The slope of the cut cake creates the illusion of the sinking ship, with the smaller acute end “going under water” and the opposite side representing the front of the ship that remains “above water”.

Again using a paper template of the shape you want, shape the front of the cake with a knife, rounding the edges gently to create the nose of the ship.

Place the ship where you want it on the cake board. An angled placing towards the back of the board works well, and leaves place for the iceberg (of course!) and other trimmings on the front of the cake.

From the parts of the removed cake, 3 rectangles of different sizes are cut or constructed to make the upper decks. Again, using paper templates for size works well. Sandwich pieces of cake together if necessary to obtain the desired height for each deck.

Roughly ice the largest rectangle onto the “hull”, leaving some deck exposed behind this piece, and with a nice large area in front of it. Ice the two remaining pieces on top of that, positioning each so as to create the upper decks effect.

As final preparation before icing, use a sharp knife to cut a small bit of cake away from the bottom front of the ship. This will create the illusion of the ship tipping backwards as it sinks, with its nose “rising” out of the water. (Hey, we believe in go big or go home – the devil really is in the detail with these things!)

Begin by icing the hull black, leaving room at the bottom of the front of the cake (especially the part that is now recessive from cutting away) to trim with red icing. Ice the deck with light brown icing. For extra effect (mom’s brilliant idea), use a knife-point, clean knitting needle, or tooth-pick to draw lines on the deck icing for a “floor board” effect.

While mom worked on the main body, I created the chimney stacks. We had originally thought of using marshmallows, but there was enough cake to use instead. If you have a narrow cake cutter, use that. I didn’t, so I cleaned and cut a tablet container (the type from the pharmacy) and used that to cut out two tubes of cake. These were iced black and red and then iced onto the top of the upper decks.

Ice the upper decks with white icing, using the knife to maintain the distinction between each deck.

At this point, you can cover the bottom layer cake with blue icing to create the sea. This is done fairly thickly and definitely roughly. Don’t forget to have the sea covering the back of the ship and “rising” over the deck.

Separate the fondant and liquorice from the yellow and white sandwich Mini Liquorice Allsorts. Cut each of the yellow fondant squares in half, and gently press the pieces into the straight part of the sides of the black hull, spacing them evenly just below the deck. These are the lower deck windows. Cut each of the liquorice squares in half and press an appropriate amount into the sides of each of the upper decks to create the windows there. Don’t forget to add windows to the front of the upper decks so the captain can see where he’s going (not that he was looking, obviously, or he wouldn’t have hit the iceberg).

We rough-cut a piece of leftover cake to create the iceberg. Ice roughly with thick water icing. (This will make the iceberg whiter than the white areas of the ship.)

Using an icing gun or piping bag, pipe a line of white icing around the deck to create the railing.

I also added a lifebuoy for fun. For this I used the middle part of an apricot marzipan sweet – broke it in half, sliced it very carefully with a knife, and made a hole in the centre. With a toothpick I added thin lines of water icing to create the ropes.

Here a just a few more photos of the finished product:

This one gives a nice view of the rough sea and how it’s breaking over the deck as the ship sinks:From the other side:Finally, we placed the candles in front of, rather than on, the cake so as not to spoil the picture created:

The glowing, wide-eyed appreciation of the birthday boy, and similar reaction from his friends, was priceless.

Making the cake (excluding the research and design phases) took about 6 hours.

8 responses to “How to Make a Sinking Ship Birthday Cake – A Pretty Titanic Task”

Thank you very much:) I really appreciate it. My son,who is a huge Titanic fan, requested a sinking Titanic as his birthday cake. I’m not very skillfull when it comes to artisctic cakes but I hope I can make it:)

Hopefully the secret simplicity of this cake will work as well for you as it did for us! I have added the cake recipe as promised, and hope your ship sinks with style! Mum’s “Isabella’s Rectangle Cake”